One of the nerve-racking things about being a student is wondering how well you must do on a final in order to earn a certain grade in your classes. If a student is keeping track of her grades throughout the year, she can predict what she needs to maintain her current grade or to raise it a letter or two. Many teachers give their pupils the percentage breakdown for their assignments by category at the beginning of the year. From this, students can calculate the grades they need for their final exam.

Step 1

Determine the average grade of each assignment category. Generally, teachers assign grades for things such as homework, quizzes, exams and the final exam. Separate these grades by category and find the average grade for each category.

Step 2

Multiply the average grade for each category by the percentage of your final grade assigned by the teacher. Therefore, if your homework grade is 20 percent of your final grade, and your average grade for your homework is 80 percent, you must multiply 80 by 20 percent. For instance, 80 x 20 percent (or 0.20) = 16. Repeat this for each assignment category and write down the product for each category.

Step 3

Add the products for each grade category. So, if your homework grade is a 16, your quiz grade is a 25 and your exam grade is a 32, when you add them you will obtain the sum of 73. Your grade, were you to get a zero on the final exam, would be a 73.

Step 4

Subtract your current grade from the grade that you want to obtain in the class. For instance, if you want to earn a 97 in the class, subtract 73 from 97. For example, 97 - 73 = 24.

Step 5

Divide the results by the percentage assigned to the final exam category. For example, if your result was 24 and the final exam is weighted as 40 percent of your final grade, you will divide 24 by 40 percent. For example, 24 / 40 percent (or 0.40) = 60. Therefore, in order to get a 97 percent in the course, you must earn a 60 percent on the final exam.